Method of measuring blood sedimentation rate



Aug. 19, 1958 H. WITT 2,848,368

METHOD OF MEASURING BLOOD SEDIMENTATION RATE Filed Aug. 20, 1953 A\\\w.I IIIIIHHIIIIIIIIIIIIIlllllllllllllll nmmwn Unite tates Patent METHOD FMEASG BLOOD SEDIIVIENTATION RATE Horst Witt, Gottingen, GermanyApplication August 20, 1953, Serial No. 375,320

2 Claims. (Cl. 16784.5)

This invention relates to a method and apparatus for the automaticrecording of the speed at which larger molecules or particles (e. g.blood cells) settle to the bottom in liquid colloidal disperse systems,such as suspensions or emulsions, e. g. blood.

With each sedimentation the homogeneous structure of the colloidaldisperse liquid (e. g. blood-blood plasma plus blood cells) existing atthe beginning of the experiment undergoes a change in such a waythat-beginning at the surface of the liquid-a column of liquid (e. g.blood plasma) which is nearly free from particles is formed by the factthat the particles (e. g. the blood I cells) sink downwards or settle tothe bottom of the recipient. In the course of time the column of liquidwhich is free from particles is steadily growing in height. The rate ofsedimentation can be stated for instance by measuring at any time theapertaining height of the liquid column which is free from particles.The height of the liquid column which is free from particles (e. g.blood plasma), however, does not increase in a linear proportion totime. In order to compare the rate of sedimentation in various colloidaldisperse liquids (e. g. blood of a sick or healthy person), the heightof the liquid column which is free from particles (e. g. blood plasma)is measured after a predetermined generally agreed period of time. Thus,for instance, according to international agreement the rate ofsedimentation of the blood is measured by the height of the column ofblood plasma after one hour. However, in practice it causes considerabletrouble to measure this height of the liquid column after apredetermined length of time.

It is an object of the present invention to provide a device whichrenders it possible to read ofi at any time the height of the plasma orother liquid column which has been existing at a predeterminedadjustable time.

A special object of the invention is to provide means for automaticallystopping the sedimentation after a predetermined adjustable period oftime.

A further object of the invention is to provide an apparatus which isadapted to heat or cool the test liquid at a predetermined time for thepurpose which will be hereinafter described.

With these and other objects in view, this invention consists in thedetails of construction, combination of elements and operationhereinafter set forth and then specifically designated by the claims.

In order that those skilled in the art to which this inventionappertains may understand how to make and use the same I will describeits construction in detail, referring by numerals to the accompanyingdrawing forming part of this application, in which:

Fig. 1 is a diagrammatic representation of an arrangement for carryingout the invention,

Figs. 2, 3, 4 and are similar diagrammatic representations showingmodified methods of heating, and

Fig. 6 is a perspective view showing a still further embodiment of theinvention.

from the vapor phase, or

Similar reference numerals denote similar parts in the differentFigures.

In order to make it clear how the apparatus according to the presentinvention works, it will be better to explain at first the principles onwhich it is based. According to the present invention the sedimentationcan be stopped in two different ways:

Either the liquid is heated to a predetermined temperature whereby incertain colloidal disperse systems, e. g. blood, the whole liquid issolidified and the sedimentation is stopped. Or the liquid is cooled toa predetermined temperature whereby the liquid freezes and thesedimentation is also stopped.

The heating of the liquid according to the present invention may beeffected by any of the following methods:

1) Electrically operated heating means are provided within or outside ofthe test tube or other vessel in which the sedimentation takes place.

(2) The test tube or other vessel in which the sedimentation takes placeconsists of an electrically conductive material. An electric current ispassed directly through the wall of the tube in order to heat theliquid.

(3) The surface of a sedimentation vessel of an electricallynon-conductive material is coated with an electrically conductive layer,for instance, of metal or metal oxide deposited on the wall of thevessel in a thin layer by a spraying or galvanizing In order to heat theliquid, passed directly through this surface process or by burning in.an electric current is layer of the vessel.

(4) The vessel in which the sedimentation takes place, is treated by theheat rays of an electric heat radiator, e. g., a glow wire.

(5) The vessel in which the sedimentation takes place is brought intoheat-exchanging relationship with a solid body, liquid bath, gas spaceor gas current of an elevated temperature.

The cooling of the liquid according to the invention may be effected insuch a way that the vessel in which the sedimentation takes place isbrought into contact with a solid body, liquid bath, gas space or gascurrent of a reduced temperature.

Referring now to the drawing in greater detail, in which these variousmethods are exemplified, it will be seen that a wire 3, Fig. 1, leadsfrom a conductor 2 of a power supply 1, 2 to a clock switch 4 which maybe driven electrically or by a spring mechanism. Provided on the movablepointer 5 of the clock switch 4 is a contact 6 which on rotation of thepointer 5 in the direction of the arrow 10 temporarily engages thecounter contact 7 from which a conductor 8 leads to one of the contactsleeves of a plug socket 11. A second wire 9 leads directly from theconductor 1 to the second contact sleeve of the plug socket 11. Thisclock switch serves to close the electric circuit at a predeterminedadjustable point of time, and for a predetermined adjustable length oftime, i. e., as long as the contact 6 engages the contact 7. This clockswitch can be used in connection with any of the heating devices shownin Figs. 1, 2, 3, and 4.

12 is a sedimentation tube having an internal free bore 13 for thereception of the particles to be deposited.

In the embodiment of my novel apparatus as per Fig. l a heating coil 14,consisting, for instance, of a chromium-nickel alloy, is arranged aroundthe tube 12 and supplied with current through two contact plugs 15adapted to be plugged into the plug socket 11.

The operation is as follows: On rotation of the pointer 5 with thecontact 6 in the direction of the arrow 10 the coil 14 is heated for acertain length of time. During this time the stopping of thesedimentation of the tube 12, i. e. the solidification of the liquidcontained therein is being efiected.

In the embodiment according to Fig. 2 an electrically operated heatradiator 16 is provided adjacent to the tube 12 for heating same. Thescale or graduation is indicated at 29 and the columns of blood plasma30 and sediment 31 are also indicated.

In the embodiment shown in Fig. 3 the tube 12 is provided with a coating17 serving as a resistance.

The coating 17 is interrupted by a slot 17a, so that the process ofsedimentation or of the stopping thereof, respectively, can be observedthrough the slot 17a.

In the embodiment shown in Fig. 4 a resistance in the form of acylindrical tube 18 is arranged around the tube 12.

Fig. shows a device in which --a heating or cooling element 19 isstationarily arranged. The test tube 12 is seated in a slide or leverwhich can be moved in the direction of the arrow 21 by action of amagnetic core 26 reaching into a solenoidal coil 27, against action of atension spring 28, so as to come into the sphere of action of theheating or cooling element 19.

In the arrangement according to Fig. 6, the tube 12 is suspended from alever 22 which can be moved in the direction of the arrows 23, by anelectromagnetic mechanism similar to that shown in Fig. 5, for dippingthe tube 12 for a certain length of time into a vessel 20 which isfilled with a heating or cooling liquid 32.

It is also possible to arrange several tubes 12 side by side in a commoncarrier lever 22 so that several sedimentation processes can be stoppedsimultaneously.

The method of solidification by heating can be applied, for instance, incase of blood which has been made noncoagulable. Blood consists amongothers of red blood cells and transparent blood plasma. The blood cellssettle in the blood plasma. With time an upper liquid column is formedwhich consists only of blood .plasma free from blood cells, while thelower liquid column consists of blood, i. e. blood plasma plus bloodcells. If the entire blood liquid is heated to 50 to 100 C., by means ofany of the arrangements shown in the figures, both the blood and thebloodplasma are solidified. After cooling to room temperature this stateis retained. This process is irreversible.

The vessel 12 is accordingly filled with the test blood, the clockswitch 4, 5, 6, 7 is adjusted to the period of time after which thesedimentation is to take place (e. g., one hour), and a contact member 6of proper length is attached to the pointer 5 so that the circuit isclosed, after the predetermined period of time, (e. g., one hour) for alength of time (e. g., one minute) which is sufiicient to causesolidification of the blood and blood plasma in the vessel. The vessel12 may now be removed from its heating device 14, or 16, or 17, or 18,or 19, or 20,

respectively, and the height of the liquid column 30, Fig. 233.

2, which has been reached after one hour, consisting, for instance, ofblood plasma containing no particles, can be read from the scale 29provided on the vessel 12, Fig. 2.

It will be understood that in case of the arrangements shown in Figs. 1to 4 the heating device itself is supplied with current for the lengthof time (e. g., one minute) required for the process of stopping thesedimentation whereas in the arrangements shown in Figs. 5 and 6 thesolenoid coil 27 is energized for this length of time to attract themagnetic core 26 and to draw the vessel 12 into the sphere of action ofthe source of heat 19, or 20, respectively.

Where the blood is to be solidified by cooling, it may be cooled down toa temperature of plus 5 C. to minus 30 C.

By way of alternative, the length of time during which the heatingdevice 14, or 16, or 17, or 18, is connected 'to the source of current1, 2, may be determined by a thermostatic device 24, Fig. 1,automatically interrupting the circuit as the desired temperature isreached.

While the invention has been described in detail with respect to certainnow preferred examples and embodiments of the invention it will beunderstood by those skilled in the art after understanding the inventionthat various changes and modifications may be made without departingfrom the spirit and scope of the invention and it is intended,therefore, to cover all such changes and modifications in the appendedclaims.

I claim:

1. In a method for measuring the rate of sedimentation in blood samples,permitting settling of red blood cells to take place in a column of thesample over a predetermined time period, and then heating the column toa temperature within the range from 50 C. to C. to irreversibly solidifythe blood and to arrest further settling whereby thereafter the heightof that portion of the column containing settled red blood cells remainsconstant.

2. A method as in claim 1 in which the heating to said temperatureoccurs within a short period .of time of the order of one minute, wherethe time period for settling is of the order of one hour.

References Cited in the file of this patent UNITED STATES PATENTS2,514,260 Rosen July 4, 1950 2,528,704 Neuda Nov. 7, .1950 2,634,359Terry Apr. 7, 1953 OTHER REFERENCES 'Todd et al.: Clinical Diagnosis byLaboratory Methods, pp. 103-106, pub. 1939, by W. B. Saunders Co.

Clinical Hematology, by M. M. Wintrobe, pp. 226-

1. IN A METHOD FOR MEASURING THE RATE OF SEDIMENTATIONS IN BLOODSAMPLES, PERMITTING SETTLING OF RED BLOOD CELLS TO TAKE PLACE IN ACOLUMN OF THE SAMPLE OVER A PREDETERMINED TIME PERIOD, AND THEN HEATINGTHE COLUMN TO A TEMPERATURE WITHIN THE RANGE FROM 50*C. TO 100*C. TOIRREVERSIBLY SOLDIFY THE BLOOD AND TO ARREST FURTHER SETTLING WHEREBYTHEREAFTER THE HEIGHT OF THE PORTION OF THE COLUMN CONTAINING SETTLEDRED BVLOOD CELLS REMAINS CONSTANT.